Runs hot

31 year old radiators are normally not helped by flushing. The small cooling tubes get plugged up and corroded to the point where they are beyond help. Also, your new engine probably exceeds the cooling capacity of your old cooling system. I would test drive it being careful to not overheat it. If it runs hot suggest putting in a larger capacity new radiator and modern electric cooling fans.......The engine compartment will really look great without the fan shroud and mechanical fan and the engine will run cool.

kenny k said:

1971 vett. With a new 383 stroker motor 365HP new water pump and checked new thermostat had the stock aluminum S/B radiator flushed and presher checked new fluids. With out the hood on an after running for 15 minutes she hits 220+degrees. Thats the car running in the shop. I'm wondering if the hood being off and car running in the shop might part of the problem or I might need a bigger radiator.thanks kk.

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I had the same problem with my '71 and I finally tracked it down to a wrong temperature sender. The '68 thru '71's used "green face" gauges that used a unique sender that had a plain round "peg" sticking out of it and a wire terminal that plugged directly onto the top of that peg. If that "round peg" sender isn't used the gauge will read a lot higher than the actual temperature. Starting in 1972 the "white face" gauge was used along with a completely different sender. Rik's stocks the correct '68 thru '71 senders under the number ENG489

Rik's has a website but you can also order by phone toll free at (888) 745-7838

kenny k said:

1971 vett. With a new 383 stroker motor 365HP new water pump and checked new thermostat had the stock aluminum S/B radiator flushed and presher checked new fluids. With out the hood on an after running for 15 minutes she hits 220+degrees. Thats the car running in the shop. I'm wondering if the hood being off and car running in the shop might part of the problem or I might need a bigger radiator.thanks kk.

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the hood being off does affect it,theres a seal between the radiator support and the hood .... as well as not moving. when you rev the engine, the fan clutch disengages..if you run it in the shop for long periods . place a fan in front of the car..drive the car and check temps before you make any changes..check the fan clutch to see if it has proper resistance when you turn the blades...the stock radiator in good condition should be adequate for your level of engine..providing you still have the fan shroud on it..

Up at Reno for "Hot August Nights" I noted that almost all the C3 cars had gone to bigger multi row radiators and electric fans and so had a lot of c2 and c1 cars.....If you end up going that route be sure to keep the original mechanical fan set up, and anything else you take off the car so it can be brought back to original easily in the future for collector value.

i have a 76 with a 468 ci bb in it and it ran hot to for the longst could not find out why, i changed radeator, 4000 cfm elect fans restrtor in thomo, hi flow water pump on and on and on , i thin got a front lower air dam frm eklers, put it on ,and yeha stop runing hot ,

Runs Hot

Hi Kenny, It's Pork Chop, I got a 72 454, Had the same thing changed every thing thrmo,cluch fan,flushed rad,new water pump,. It came down to the fome around the rad. If the air don't go directly throught the Rad it won't stay cool. It a cheep fix.:wtf::z1-2:

Thats what I was referring to above.. that little foam seal between the hood and radiator support is necessary.

Thank you for the good advice, she runs under 180 now. Thanks k.k.